PROJECT SUMMARY: Botswana has the second-highest HIV prevalence in the world. Low-cost, scalable interventions are essential to support people living with HIV to adhere to antiretroviral treatment (ART) and remain in care. One such intervention is the use of treatment partners, which are recommended by HIV treatment guidelines in at least 20 countries worldwide. Specifically, national HIV policies of several countries, including Botswana, recommend that healthcare providers encourage patients initiating ART to identify an individual who can provide support, accompany patients to appointments, and provide medication reminders. Although a large body of work indicates the key role of social support in promoting adherence, research on treatment partners' effectiveness has shown mixed results. Thus, research is needed to determine how support from treatment partners can be better harnessed. Our R21 study examined optimal characteristics of treatment partners. Results indicated that effective treatment partners not only help with adherence, but also provide essential non-medical support (e.g., transport, food preparation), and that effective treatment partners are more likely to be spouses or other intimate partners than other types of network members. Treatment partners, especially of unsuppressed patients, requested counseling skills training. Using our R21 as a basis, we propose to pilot test the effects of the Mopati program (?partner? in Setswana, the official language of Botswana), a multi-level intervention that guides healthcare providers and patients about treatment partner selection, and trains treatment partners on provision of effective support. The Specific Aims are: (1) To develop a multi-level treatment partner intervention with input from community and healthcare provider stakeholders in Botswana; and (2) To conduct a pilot test of the feasibility, acceptability, and preliminary effects on viral suppression of a multi-level treatment partner intervention. We will recruit 80 people living with HIV who are not virally suppressed and their 80 treatment partners in 2 matched clinic pairs (4 clinics total; 20 dyads/clinic) in Gaborone, Botswana. Clinics will be randomly assigned to standard of care or a healthcare provider guidance and treatment partner training intervention (i.e., all clinic providers receive training on advising patients about treatment partner selection, and all treatment partners receive HIV treatment education and training on counseling patients using a non-confrontational, non-judgmental style). We will survey patients and treatment partners at baseline and 6-months post-baseline and collect viral load from clinic records. Intervention feasibility and acceptability will be assessed via mixed methods (e.g., semi-structured interviews with patients, treatment partners, and clinic staff; refusal rates). We will present results to the committee that develops the Botswana National HIV and AIDS Treatment Guidelines. This research presents a unique opportunity to examine ways to improve ART use in practice across countries and has relevance for both HIV- care as well as healthcare for other conditions (e.g., diabetes, tuberculosis) that require strict adherence.